Databricks Certified Data Engineer Professional Practice Test 12
Question 110
A deployment owner at Cedar Brook Commerce needs to implement a remedy: multiple engineering teams ship notebook and Python tasks to separate workspaces. The present failure is: Source files and deployment definitions are coupled to one developer workspace. Which change should be applied?
- Update the task dependency list and deploy a tested wheel or requirements set
- Move task source under version control and declare jobs or pipelines in bundle resources
- Use the Databricks CLI to validate and deploy the bundle target
- Set silver task depends_on edges pointing to the bronze task
Explanation
Correct Answer
B:Move task source under version control and declare jobs or pipelines in bundle resources. This directly changes the feature or logic behind source files and deployment definitions are coupled to one developer workspace. A versioned Declarative Automation Bundle defines code and resource configurations separately from the target workspace. It is the concrete configuration for the stated incident.
Incorrect Answers
A:Update the task dependency list and deploy a tested wheel or requirements set. This implement action addresses a different case (library version pinning), where a transitive dependency updated to an incompatible version. Explicit compatible dependency versions improve reproducibility across new compute environments. In the stated problem, source files and deployment definitions are coupled to one developer workspace; this choice would not establish the required bundle repository layout decision.
C:Use the Databricks CLI to validate and deploy the bundle target. This implement action addresses a different case (databricks cli resource updates), where production configuration drifts from repository source definitions. Declarative deployment describes resources as reviewed version-controlled artifacts. In the stated problem, source files and deployment definitions are coupled to one developer workspace; this choice would not establish the required bundle repository layout decision.
D:Set silver task depends_on edges pointing to the bronze task. This implement action addresses a different case (job task dag), where dependent tasks sometimes run before the bronze load finishes. Lakeflow Job task dependencies form a directed acyclic execution graph. In the stated problem, source files and deployment definitions are coupled to one developer workspace; this choice would not establish the required bundle repository layout decision.
Question 111
Quality assurance at Silver Ridge Logistics checks a corrected workload where a batch aggregation spills because a few shuffle partitions hold too much data. The original fault was: The current partition count is too low for data volume. Which verification is most decisive?
- Benchmark light and heavy runs to verify runtime and cost objectives
- Confirm partition scan count falls with equal query results
- Verify shuffle spill decreases without excessive scheduling overhead
- Compare file count and query result checksums before and after
Explanation
Correct Answer
C:Verify shuffle spill decreases without excessive scheduling overhead. This tests the expected result against the current partition count is too low for data volume, not simply whether a job or object exists. Shuffle partition sizing affects memory pressure and task parallelism.
Incorrect Answers
A:Benchmark light and heavy runs to verify runtime and cost objectives. This validate action addresses a different case (autoscaling right-size), where a fixed high-worker count wastes resources on quiet days. Supported autoscaling can adapt worker count within configured bounds. In the stated problem, the current partition count is too low for data volume; this choice would not establish the required shuffle partition count decision.
B:Confirm partition scan count falls with equal query results. This validate action addresses a different case (partition pruning), where a query wraps business_date in a transformation and reads many partitions. Direct predicates on partition keys can enable partition pruning. In the stated problem, the current partition count is too low for data volume; this choice would not establish the required shuffle partition count decision.
D:Compare file count and query result checksums before and after. This validate action addresses a different case (small file compaction), where read overhead grows because query plans open excessive small files. OPTIMIZE can compact compatible Delta files without changing logical table contents. In the stated problem, the current partition count is too low for data volume; this choice would not establish the required shuffle partition count decision.
Question 112
At Silver Ridge Logistics, developers need to test pipeline code without altering production governance controls. The known risk is: All developers currently own production catalogs and can grant access. After remediation, which ongoing signal best detects recurrence?
- Monitor view definition changes and access to raw source
- Audit token service access and key rotation schedules
- Monitor new external-location grants and credential usage
- Audit ownership changes and privilege grants
Explanation
Correct Answer
D:Audit ownership changes and privilege grants. This watches the failure mode described by all developers currently own production catalogs and can grant access. Separate deploy and governance roles reduce accidental privilege escalation. It supplies a regression signal after remediation.
Incorrect Answers
A:Monitor view definition changes and access to raw source. This monitor action addresses a different case (sensitive data suppression), where a broad SELECT still includes unstructured notes. Column suppression and data minimization prevent unnecessary sensitive-field release. In the stated problem, all developers currently own production catalogs and can grant access; this choice would not establish the required separation of duties decision.
B:Audit token service access and key rotation schedules. This monitor action addresses a different case (pseudonymized join keys), where a naive hash without controlled key management risks predictable identifiers. Keyed pseudonymization can preserve joins while reducing identifier exposure. In the stated problem, all developers currently own production catalogs and can grant access; this choice would not establish the required separation of duties decision.
C:Monitor new external-location grants and credential usage. This monitor action addresses a different case (storage credential scope), where engineers propose a credential allowing access to all company buckets. Unity Catalog storage credentials and external locations can constrain storage access. In the stated problem, all developers currently own production catalogs and can grant access; this choice would not establish the required separation of duties decision.
Question 113
At Orion Capital, a group creates many tables in random external paths. Observed issue: The data platform cannot apply consistent lifecycle governance. Before applying a fix, which investigation is most directly relevant?
- Inspect catalog and schema managed-location settings
- Inspect catalog BROWSE and SELECT grants for the discovery group
- Inspect current owner and authorized ownership transfer process
- Inspect lineage graph from the gold table to upstream datasets
Explanation
Correct Answer
A:Inspect catalog and schema managed-location settings. This checks the specific evidence behind the data platform cannot apply consistent lifecycle governance. Managed locations centralize storage ownership for Unity Catalog managed assets. The investigation distinguishes the mechanism from an unrelated operational symptom.
Incorrect Answers
B:Inspect catalog BROWSE and SELECT grants for the discovery group. This diagnose action addresses a different case (browse metadata privilege), where teams grant SELECT merely to expose object listings. BROWSE enables controlled metadata discovery without granting data read access. In the stated problem, the data platform cannot apply consistent lifecycle governance; this choice would not establish the required managed storage ownership decision.
C:Inspect current owner and authorized ownership transfer process. This diagnose action addresses a different case (ownership reassignment), where new data stewards cannot maintain its grants. Unity Catalog ownership should be assigned to a maintained principal. In the stated problem, the data platform cannot apply consistent lifecycle governance; this choice would not establish the required managed storage ownership decision.
D:Inspect lineage graph from the gold table to upstream datasets. This diagnose action addresses a different case (lineage tracking), where investigators cannot tell which upstream transformation produced it. Unity Catalog lineage records relationships between governed data assets. In the stated problem, the data platform cannot apply consistent lifecycle governance; this choice would not establish the required managed storage ownership decision.
Question 114
At Granite Edge Labs, a complex aggregation fails repeatedly under memory pressure. The known risk is: Operators increase driver memory but failures occur on executors. After remediation, which ongoing signal best detects recurrence?
- Monitor test failures and bypassed approval controls
- Monitor spill, OOM and failed-task distribution
- Monitor dependency-related task failure signatures
- Monitor repeated repairs and remaining downstream failures
Explanation
Correct Answer
B:Monitor spill, OOM and failed-task distribution. This watches the failure mode described by operators increase driver memory but failures occur on executors. Spark UI task failures and shuffle/spill metrics distinguish worker pressure from driver issues. It supplies a regression signal after remediation.
Incorrect Answers
A:Monitor test failures and bypassed approval controls. This monitor action addresses a different case (ci quality gates), where the deployment pipeline only checks YAML syntax. CI must run transformation tests and controlled integration checks before deployment. In the stated problem, operators increase driver memory but failures occur on executors; this choice would not establish the required spark ui failure stage decision.
C:Monitor dependency-related task failure signatures. This monitor action addresses a different case (cluster log diagnostics), where the notebook cell shows only a generic stage failure. Driver and executor logs often contain the exact import or JVM error. In the stated problem, operators increase driver memory but failures occur on executors; this choice would not establish the required spark ui failure stage decision.
D:Monitor repeated repairs and remaining downstream failures. This monitor action addresses a different case (repair failed tasks), where operators rerun the entire job and duplicate completed side effects. Repair runs can rerun failed or selected tasks while preserving successful predecessor work under supported semantics. In the stated problem, operators increase driver memory but failures occur on executors; this choice would not establish the required spark ui failure stage decision.
Question 115
At Meadowland Software, a CI pipeline modifies jobs through ad hoc unversioned API calls. Observed issue: Production configuration drifts from repository source definitions. Before applying a fix, which investigation is most directly relevant?
- Compare notebook and cluster package versions and import origins
- Compare job parameter definitions to hard-coded notebook literals
- Compare deployed job JSON with the version-controlled bundle
- Inspect repository paths and bundle deployment definitions for hard-coded workspace identifiers
Explanation
Correct Answer
C:Compare deployed job JSON with the version-controlled bundle. This checks the specific evidence behind production configuration drifts from repository source definitions. Declarative deployment describes resources as reviewed version-controlled artifacts. The investigation distinguishes the mechanism from an unrelated operational symptom.
Incorrect Answers
A:Compare notebook and cluster package versions and import origins. This diagnose action addresses a different case (library precedence), where a notebook-scoped installation overrides the expected cluster version. The runtime can resolve conflicting versions from different installation scopes. In the stated problem, production configuration drifts from repository source definitions; this choice would not establish the required databricks cli resource updates decision.
B:Compare job parameter definitions to hard-coded notebook literals. This diagnose action addresses a different case (job parameters), where code contains hard-coded region IDs and catalog names. Task parameters allow runtime-specific values without changing notebook source. In the stated problem, production configuration drifts from repository source definitions; this choice would not establish the required databricks cli resource updates decision.
D:Inspect repository paths and bundle deployment definitions for hard-coded workspace identifiers. This diagnose action addresses a different case (bundle repository layout), where source files and deployment definitions are coupled to one developer workspace. A versioned Declarative Automation Bundle defines code and resource configurations separately from the target workspace. In the stated problem, production configuration drifts from repository source definitions; this choice would not establish the required databricks cli resource updates decision.
Question 116
At Silver Ridge Logistics, a batch aggregation spills because a few shuffle partitions hold too much data. Architecture constraint: The current partition count is too low for data volume. Which design best addresses this requirement?
- Choose adaptive skew join handling or a justified hot-key strategy
- Select bounded autoscaling that protects peak latency without large idle capacity
- Choose a supported columnar Delta or Parquet layout for analytics
- Choose a partition count based on volume and executor capacity
Explanation
Correct Answer
D:Choose a partition count based on volume and executor capacity. This design addresses the current partition count is too low for data volume. Shuffle partition sizing affects memory pressure and task parallelism. It establishes the right contract or architecture before execution changes.
Incorrect Answers
A:Choose adaptive skew join handling or a justified hot-key strategy. This design action addresses a different case (skewed joins), where a single join partition spills heavily to disk. Adaptive skew handling or key salting can mitigate a hot join key. In the stated problem, the current partition count is too low for data volume; this choice would not establish the required shuffle partition count decision.
B:Select bounded autoscaling that protects peak latency without large idle capacity. This design action addresses a different case (autoscaling right-size), where a fixed high-worker count wastes resources on quiet days. Supported autoscaling can adapt worker count within configured bounds. In the stated problem, the current partition count is too low for data volume; this choice would not establish the required shuffle partition count decision.
C:Choose a supported columnar Delta or Parquet layout for analytics. This design action addresses a different case (columnar compression), where row-oriented text storage increases scans and transfer volumes. Columnar formats and appropriate encoding improve analytical read efficiency. In the stated problem, the current partition count is too low for data volume; this choice would not establish the required shuffle partition count decision.
Question 117
A deployment owner at Cobalt Biotech needs to implement a remedy: a bronze layer ingests immutable audit event files. The present failure is: A nightly overwrite accidentally removes historical audit events. Which change should be applied?
- Replace overwrite with append and enable any appropriate guardrails
- Read objects with the supported binaryFile source and retain content/path fields
- Configure cloudFiles ingestion into a Delta bronze streaming table
- Configure the Kafka stream and persistent checkpoint path
Explanation
Correct Answer
A:Replace overwrite with append and enable any appropriate guardrails. This directly changes the feature or logic behind a nightly overwrite accidentally removes historical audit events. Append-only ingestion keeps previous raw records while adding new batches. It is the concrete configuration for the stated incident.
Incorrect Answers
B:Read objects with the supported binaryFile source and retain content/path fields. This implement action addresses a different case (binary payload metadata), where a line-oriented text reader corrupts the raw binary payload. binaryFile input preserves raw file bytes and path metadata rather than decoding lines. In the stated problem, a nightly overwrite accidentally removes historical audit events; this choice would not establish the required append-only delta bronze decision.
C:Configure cloudFiles ingestion into a Delta bronze streaming table. This implement action addresses a different case (auto loader file discovery), where listing the full historical directory every run exceeds the ingestion SLA. Auto Loader is designed for incremental new-file discovery with persisted state. In the stated problem, a nightly overwrite accidentally removes historical audit events; this choice would not establish the required append-only delta bronze decision.
D:Configure the Kafka stream and persistent checkpoint path. This implement action addresses a different case (kafka offset durability), where restarting with a fresh checkpoint replays previously ingested messages. A stable streaming checkpoint maintains Kafka offsets and sink progress across restarts. In the stated problem, a nightly overwrite accidentally removes historical audit events; this choice would not establish the required append-only delta bronze decision.
Question 118
Operations at Clearstone Media owns a workload where two datasets are joined to create a daily fact table. The previously identified issue was: The row count doubles because the right side contains duplicate join keys. Which metric or audit check best detects drift?
- Monitor state rows and dropped late-event counts
- Track right-side duplicate-key rate across loads
- Track dependency upgrades and compatibility test failures
- Monitor duplicate business keys and retry/batch-ID counts
Explanation
Correct Answer
B:Track right-side duplicate-key rate across loads. This watches the failure mode described by the row count doubles because the right side contains duplicate join keys. A many-to-many join expands cardinality unless the right grain is established. It supplies a regression signal after remediation.
Incorrect Answers
A:Monitor state rows and dropped late-event counts. This monitor action addresses a different case (event-time watermarking), where old keys remain in state indefinitely without a lateness bound. Watermarks provide a lateness threshold for bounded stateful streaming operations. In the stated problem, the row count doubles because the right side contains duplicate join keys; this choice would not establish the required sql join cardinality decision.
C:Track dependency upgrades and compatibility test failures. This monitor action addresses a different case (library version pinning), where a transitive dependency updated to an incompatible version. Explicit compatible dependency versions improve reproducibility across new compute environments. In the stated problem, the row count doubles because the right side contains duplicate join keys; this choice would not establish the required sql join cardinality decision.
D:Monitor duplicate business keys and retry/batch-ID counts. This monitor action addresses a different case (streaming idempotent sink), where a retry of a completed batch produces duplicate sink rows. foreachBatch can execute a batch again and requires idempotent external writes for exactly-once effects. In the stated problem, the row count doubles because the right side contains duplicate join keys; this choice would not establish the required sql join cardinality decision.
Question 119
Operations at Northfield Analytics owns a workload where a streaming table may accept only rows with nonnull transaction IDs. The previously identified issue was: Invalid rows currently reach downstream aggregates. Which metric or audit check best detects drift?
- Alert on increasing quarantine rates and source schemas
- Monitor cast failure and schema drift counts
- Monitor expectation-drop counts and upstream correction rates
- Alert when active-key uniqueness violations recur
Explanation
Correct Answer
C:Monitor expectation-drop counts and upstream correction rates. This watches the failure mode described by invalid rows currently reach downstream aggregates. A Lakeflow expectation configured to drop invalid rows filters violations from target output. It supplies a regression signal after remediation.
Incorrect Answers
A:Alert on increasing quarantine rates and source schemas. This monitor action addresses a different case (quarantine bad records), where dropping invalid rows silently hides upstream quality failures. Quarantine preserves invalid events separately while allowing valid records through. In the stated problem, invalid rows currently reach downstream aggregates; this choice would not establish the required expectation drop action decision.
B:Monitor cast failure and schema drift counts. This monitor action addresses a different case (silver schema enforcement), where implicit type coercion risks invalid numeric values being stored. Schema validation and explicit casts make type conversion failures observable. In the stated problem, invalid rows currently reach downstream aggregates; this choice would not establish the required expectation drop action decision.
D:Alert when active-key uniqueness violations recur. This monitor action addresses a different case (uniqueness quality rule), where an upstream replay creates multiple active versions. An explicit uniqueness check identifies duplicate business keys before serving data. In the stated problem, invalid rows currently reach downstream aggregates; this choice would not establish the required expectation drop action decision.
Question 120
A deployment owner at Clearstone Media needs to implement a remedy: a product dimension adds a new optional classification attribute. The present failure is: A destructive table recreation would invalidate downstream consumers. Which change should be applied?
- Create governed dimension tables and stable foreign keys in the fact
- Map both marts to the governed conformed dimension
- On change, close the prior version and insert a new dimension version
- Alter the dimension schema and backfill the new field safely
Explanation
Correct Answer
D:Alter the dimension schema and backfill the new field safely. This directly changes the feature or logic behind a destructive table recreation would invalidate downstream consumers. Additive schema evolution can preserve contracts when null defaults are acceptable. It is the concrete configuration for the stated incident.
Incorrect Answers
A:Create governed dimension tables and stable foreign keys in the fact. This implement action addresses a different case (star schema analytics), where a denormalized mixed-grain table produces redundant attributes and expensive corrections. A star schema links a clear-grain fact to reusable dimensions for consistent analytics. In the stated problem, a destructive table recreation would invalidate downstream consumers; this choice would not establish the required dimension evolution decision.
B:Map both marts to the governed conformed dimension. This implement action addresses a different case (conformed dimensions), where the same country appears under conflicting dimension keys across marts. A conformed dimension provides common attribute definitions across fact models. In the stated problem, a destructive table recreation would invalidate downstream consumers; this choice would not establish the required dimension evolution decision.
C:On change, close the prior version and insert a new dimension version. This implement action addresses a different case (scd type 2 effective dates), where a single current tier overwrites history in the dimension. SCD Type 2 stores effective start/end intervals for distinct historical dimension versions. In the stated problem, a destructive table recreation would invalidate downstream consumers; this choice would not establish the required dimension evolution decision.